Big thanks to Pi73i for the Arctic Clean suggestion! I was able to dissolve the thermal glue residue just enough to be able to scrape it off with a credit card. Here are the results!
The fittings. What surprises me the most is how heavy these things are. They feel very solid and high quality.
I read that It was recommended to flush the system before hooking up everything together so I gave each piece an individual rinse with some warm distilled water. I filled each radiator and block, sealed it, shook it for about 10 minutes and then emptied the distilled water out. Lots of flux in the radiators, so I'm glad I did that!
GPU blocks in serial configuration. Is parallel better?
Flow meter. Unsure of where to hook this up in the motherboard to be able to monitor the flow. Anyone have any advice on this?
Drain mechanism at the lowest point in the loop.
Since this is my first water-cooling build, I decided to practice with some spare tubing that I got form home depot in the hopes of discovering some subtleties that can only be learned though practice haha.
This contraption is how the water will be coming in to the radiator form the pump. Its long enough that it comes out through the cable routing hole in the case.
Radiators and fans installed in the case. I am pretty sure there is enough room to do a push pull on the top radiator. Might consider doing that down the line.